Mobile device control

ABSTRACT

A system includes a processor coupled to a memory, the processor and memory configured to determine a proficiency level of a user of a rescue application based on stored data indicative of the user&#39;s proficiency level, and based on the user&#39;s proficiency level, select a level of operation for the rescue application. The rescue application is executed on a mobile device and configured to control operation of an AED. Each of multiple levels of operation for the rescue application allows the user a different degree of control over the operation of the AED. The processor and memory are configured to present, to the user, a set of instructions associated with the selected level of operation; and to enable control of the AED according to the selected levels of operation. A different set of instructions is associated with each of the multiple levels.

TECHNICAL FIELD

This invention relates to resuscitation systems incorporatingdefibrillation therapy and resuscitation prompts.

BACKGROUND

Resuscitation can generally include clearing a patient's airway,assisting the patient's breathing, chest compressions, anddefibrillation.

The American Heart Association's Basic Life Support for Health CareProviders textbook provides a flow chart at page 4-14 of Chapter 4 thatlists the steps of airway clearing, breathing, and circulation (known asA, B, and C), for situations in which there is no defibrillator readilyaccessible to the rescuer.

Defibrillation (sometimes known as step D) can be performed with the useof an automatic external defibrillator (AED). Most automatic externaldefibrillators are actually semi-automatic external defibrillators(SAED), which require a clinician to press a start button, after whichthe defibrillator analyzes the patient's condition and provides a shockto the patient if the electrical rhythm is shockable and waits for userintervention before any subsequent shock. Fully automatic externaldefibrillators, on the other hand, do not wait for user interventionbefore applying subsequent shocks. As used below, automatic externaldefibrillators (AED) include semi-automatic external defibrillators(SAED).

Both types of defibrillators typically provide an oral stand clearwarning before the application of each shock, and then the clinician isexpected to stand clear of the patient and may be required to press abutton indicating that the clinician is standing clear of the patient.The controls for automatic external defibrillators are typically locatedon a resuscitation control box.

AEDs are used typically by trained providers such as physicians, nurses,fire department personnel, and police officers. There might be one ortwo people at a given facility that has an AED who have been designatedfor defibrillation resuscitation before an ambulance service arrives.The availability of on-site AEDs along with rescuers trained to operatethem is important because if the patient experiences a delay of morethan 4 minutes before receiving a defibrillation shock the patient'schance of survival can drop dramatically. Many large cities and ruralareas have low survival rates for defibrillation because the ambulanceresponse time is slow, although many suburbs have higher survival ratesbecause of the faster ambulance response time due to lack of traffic andavailability of hospitals and advanced life support.

Trained lay providers are a new group of AED operators, but they rarelyhave opportunities to defibrillate. For example, spouses of heart attackvictims may become lay providers, but these lay providers can be easilyintimidated by an AED during a medical emergency. Consequently, such layproviders can be reluctant to purchase AEDs, or might tend to wait foran ambulance to arrive rather than use an available AED, out of concernthat the lay provider might do something wrong.

There are many different kinds of heart rhythms, some of which areconsidered shockable and some of them are not. For example, a normalrhythm is considered non-shockable, and there are also many abnormalnon-shockable rhythms. There are also some abnormal non-viablenon-shockable, which means that the patient cannot remain alive with therhythm, but yet applying shocks will not help convert the rhythm.

As an example of a non-shockable rhythm, if a patient experiencesasystole, the heart will not be beating and application of shocks willbe ineffective. Pacing is recommended for asystole, and there are otherthings that an advanced life support team can do to assist such patient,such as the use of drugs. The job of the first responder is simply tokeep the patient alive, through the use of CPR and possiblydefibrillation, until an advanced life support team arrives.Bradycardias, during which the heart beats too slowly, are non-shockableand also possibly non-viable. If the patient is unconscious duringbradycardia, it can be helpful to perform chest compressions untilpacing becomes available. Electro-mechanical dissociation (EMD), inwhich there is electrical activity in the heart but it is not making theheart muscle contract, is non-shockable and non-viable, and wouldrequire CPR as a first response. Idio-ventricular rhythms, in which thenormal electrical activity occurs in the ventricles but not the atria,can also be non-shockable and non-viable (usually, abnormal electricalpatterns begin in the atria). Idio-ventricular rhythms typically resultin slow heart rhythms of 30 or 40 beats per minute, often causing thepatient to lose consciousness. The slow heart rhythm occurs because theventricles ordinarily respond to the activity of the atria, but when theatria stop their electrical activity, a slower, backup rhythm occurs inthe ventricles.

The primary examples of shockable rhythms, for which a first respondershould perform defibrillation, include ventricular fibrillation,ventricular tachycardia, and ventricular flutter.

After using a defibrillator to apply one or more shocks to a patient whohas a shockable electrical rhythm, the patient may nevertheless remainunconscious, in a shockable or non-shockable rhythm. The rescuer maythen resort to chest compressions. As long as the patient remainsunconscious, the rescuer can alternate between use of the defibrillator(for analyzing the electrical rhythm and possibly applying a shock) andperforming cardio-pulmonary resuscitation (CPR).

CPR generally involves a repeating pattern of chest compressionsfollowed by a pause. CPR is generally ineffective against abnormalrhythms, but it does keep some level of blood flow going to thepatient's vital organs until an advanced life support team arrives. Itis difficult to perform CPR over an extended period of time. Certainstudies have shown that over a course of minutes, rescuers tend toperform chest compressions with less-than-sufficient strength to causean adequate supply of blood to flow to the brain. CPR prompting devicescan assist a rescuer by prompting each chest compression and breath.

PCT Patent Publication No. WO 99/24114, filed by Heartstream, Inc.,discloses an external defibrillator having PCR and ACLS (advancedcardiac life support) prompts.

SUMMARY

In a general aspect, a system includes a processor coupled to a memory,the processor and memory configured to determine a proficiency level ofa user of a rescue application based on stored data indicative of theuser's history of use of the rescue application, select a level ofoperation for the rescue application. The rescue application is executedon a mobile device and configured to control operation of a AED. Each ofmultiple levels of operation for the rescue application allows the usera different degree of control over the operation of the AED. Theprocessor and memory are configured to present, to the user, a set ofinstructions associated with the selected level of operation. Adifferent set of instructions is associated with each of the multiplelevels. The processor and memory are configured to enable control of theAED according to the selected levels of operation.

In a general aspect, a system includes a processor coupled to a memory,the processor and memory configured to determine a proficiency level ofa user of a rescue application based on stored data indicative of theuser's proficiency level, and based on the user's proficiency level,select a level of operation for the rescue application. The rescueapplication is executed on a mobile device and configured to controloperation of an AED. Each of multiple levels of operation for the rescueapplication allows the user a different degree of control over theoperation of the AED. The processor and memory are configured topresent, to the user, a set of instructions associated with the selectedlevel of operation. A different set of instructions is associated witheach of the multiple levels. The processor and memory are configured toenable control of the AED according to the selected levels of operation.

In a general aspect, a system includes a processor coupled to a memory,the processor and memory configured to, based on a proficiency level ofa user of a rescue application, select a level of operation for therescue application. The rescue application is executed on a mobiledevice and configured to control operation of a treatment unit. Theprocessor and memory are configured to enable control of the treatmentunit according to the selected level of operation.

Embodiments can include one or more of the following features.

Each of multiple levels of operation allows the user a different degreeof control over the operation of the treatment unit.

The treatment unit includes an AED.

The processor and memory are is configured to, based on the level ofoperation, select a particular set of instructions from multiple sets ofinstructions to present to the user.

The processor and memory are configured to receive data about a patientbeing treated by the treatment unit. The processor and memory areconfigured to select at least some of the data for display on a displayinterface based on the level of operation. In some cases, the data isreceived from a multiple lead ECG.

The processor and memory are configured to receive an indication toexecute the rescue application in either a rescue mode or a trainingmode. In some cases, when the rescue application is executed in trainingmode, enabling control of the treatment unit includes enablingsimulation of the operation of the treatment unit. In some cases, whenthe rescue application is executed in rescue mode, enabling control ofthe treatment unit includes establishing a connection with an AED; andsending a control signal to the AED.

The proficiency level of the user is based on the user's history ofusing the rescue application.

The processor and memory are configured to increase the user'sproficiency level when the user satisfies a metric associated with therescue application.

The memory is configured to store data indicative of the user's historyof using the rescue application. The processor and memory are configuredto, based on the stored data, determine when the user has satisfied themetric. In some cases, the metric includes a metric associated with aparticular one of the levels of operation of the rescue application.

Enabling control of the treatment unit includes automaticallycontrolling the treatment unit.

Enabling control of the treatment unit includes controlling theoperation of the treatment unit according to a command received from theuser.

Enabling control of the treatment unit includes controlling thetreatment unit to analyze a condition of a patient, to deliver a shockto the patient, or both.

In a general aspect, a computer readable medium stores instructions forcausing a computing system to, based on a proficiency level of a user ofa rescue application, select a level of operation for the rescueapplication; and enable control of the treatment unit according to theselected level of operation. The rescue application is executed on amobile device and configured to control operation of a treatment unit.

Embodiments can include one or more of the following features.

Each of multiple levels of operation allows the user a different degreeof control over the operation of the treatment unit.

The treatment unit includes an AED.

The instructions cause the computing system to, based on the level ofoperation, select a particular set of instructions from multiple sets ofinstructions to present to the user.

The instructions cause the computing system to receive data about apatient being treated by the treatment unit; and select at least some ofthe data for display on a display interface based on the level ofoperation. In some cases, the data is received from a multiple lead ECG.

The instructions cause the computing system to receive an indication toexecute the rescue application in either a rescue mode or a trainingmode. In some cases, when the rescue application is executed in trainingmode, enabling control of the treatment unit includes enablingsimulation of the operation of the treatment unit. In some cases, whenthe rescue application is executed in rescue mode, enabling control ofthe treatment unit includes establishing a connection with an AED; andsending a control signal to the AED.

The proficiency level of the user is based on the user's history ofusing the rescue application.

The instructions cause the computing system to increase the user'sproficiency level when the user satisfies a metric associated with therescue application. In some cases, the instructions cause the computingsystem to store data indicative of the user's history of using therescue application; and based on the stored data, determine when theuser has satisfied the metric. In some cases, the metric includes ametric associated with a particular one of the levels of operation ofthe rescue application.

The instructions for causing the computing system to enable control ofthe treatment unit include instructions for causing the computing systemto automatically control the treatment unit.

The instructions for causing the computing system to enable control ofthe treatment unit include instructions for causing the computing systemto control the operation of the treatment unit according to a commandreceived from the user.

The instructions for causing the computing system to enable control ofthe treatment unit include instructions for causing the computing systemto control the treatment unit to analyze a condition of a patient, todeliver a shock to the patient, or both.

In a general aspect, a method includes determining a proficiency levelof a user of a rescue application based on stored data indicative of theuser's proficiency level. The rescue application is executed on a mobiledevice and configured to control operation of a AED. The methodincludes, based on the user's proficiency level, selecting a level ofoperation for the rescue application. Each of multiple levels ofoperation for the rescue application allows the user a different degreeof control over the operation of the AED. The method includespresenting, to the user, a set of instructions associated with theselected level of operation, wherein a different set of instructions isassociated with each of the multiple levels; and enabling control of theAED according to the selected levels of operation.

The techniques described herein can have one or more of the followingadvantages. Providing control of a treatment unit, such as an AED, froma mobile computing device is convenient and allows users to deliverrescue treatments through a familiar interface. Users can practicetreatment delivery using the mobile computing device as a simulator togain experience outside of real emergency situations. Mobile computingdevices can offer capabilities for powerful control of AEDs and othertreatment and monitoring techniques. The capabilities that areaccessible to a given user are tailored to the user's level ofexperience, thus helping to ensure that the user is provided with toolsto deliver safe and effective treatment to a patient.

A portable ECG package allows medical personnel to carry around complexmultiple lead ECG equipment, e.g., a 12-lead ECG, without the danger ofdamaging the ECG electrodes or tangling the ECG cables.

The details of one or more embodiments are set forth in the accompanyingdrawings and the description below. Other features and advantages willbe apparent from the description, drawings, and claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a drawing of a defibrillation electrode pad according to the

invention, positioned over the chest of a patient.

FIG. 2 is a view of the front display panel of a resuscitation controlbox according to the invention that houses electronic circuitry andprovides audible and visual prompting.

FIG. 3 is a cross-sectional drawing of the defibrillation electrode padof FIG. 1 taken along line 3-3.

FIG. 4 is a cross-sectional drawing of the defibrillation pad of FIG. 1taken along line 4-4.

FIG. 5 is a circuit diagram illustrating the circuit interconnectionsbetween the defibrillation electrode pad of FIG. 1 and the resuscitationcontrol box of FIG. 2 .

FIGS. 6A and 6B are a flowchart illustrating the initial routine of aresuscitation system according to the invention.

FIGS. 7A, 7B, and 7C are a flowchart illustrating the “circulation help”routine of the resuscitation system.

FIG. 8 is a flowchart illustrating the “breathing help” routine of theresuscitation system.

FIGS. 9A and 9B are a flowchart illustrating the “airway help” routineof the resuscitation system.

FIG. 10 is a block diagram of the electronic circuitry of an alternativeimplementation.

FIG. 11 is a drawing of the defibrillation electrode assembly of anotheralternative.

FIGS. 12A-12C are diagrammatic views of three possible implementationsof first and second units.

FIGS. 13A and 13B are drawings of two alternative implementations of theelectrode pad assembly in which a handle is provided for the rescuer.

FIG. 14 is a diagram of a treatment unit and a control unit.

FIG. 15 is a flowchart.

FIG. 16 is a chart of example levels of operation of a control unit app.

FIGS. 17-19 are flowcharts.

FIGS. 20-23 are diagrams of a portable multiple lead ECG package.

FIG. 24 is a flowchart.

DETAILED DESCRIPTION

With reference to FIG. 1 , a defibrillation electrode pad 10, whichincludes high-voltage apex defibrillation electrode 12 and high-voltagesternum defibrillation electrode 14, is placed on the patient's chest 16and includes a region 18 on which a user may press to perform CPR.Legends on pad 10 indicate proper placement of the pad with respect tothe patient's collarbones and the chest centerline and the properplacement of the heel of the rescuer's hand.

A low-profile button panel 20 is provided on the electrode assembly.Button panel 20 has buttons 22, including buttons A (Airway Help), B(Breathing Help), C (Circulation Help) and PAUSE, and may also includeadjacent light emitting diodes (LEDs) 24 that indicate which button hasbeen most recently pressed. Button panel 20 is connected by a cable 23to a remote resuscitation control box 26, shown in FIG. 2 . Button panel20 provides rigid support underneath buttons A, B, C, and PAUSE againstwhich the switches can be pushed in order to ensure good switch closurewhile the electrode rests on a patient. Button panel 20 includescomponents that make electrical contact with silver/silver-chlorideelectrical circuit components screen-printed on a polyester base ofdefibrillation electrode pad 10, as is described in detail below.

A pulse detection system based on shining light through the patient'svascular bed, e.g., a pulse oximetry system 52, is incorporated intodefibrillation electrode pad 10. Pulse oximetry system 52 includes a redlight-emitting diode, a near-infrared light-emitting diode, and aphotodetector diode (see FIG. 5 ) incorporated into defibrillationelectrode pad 10 in a manner so as to contact the surface of thepatient's chest 16. The red and near-infrared light-emitting diodes emitlight at two different wavelengths, which is diffusely scattered throughthe patient's tissue and detected by the photodetector diode. Theinformation obtained from the photodetector diode can be used todetermine whether the patient's blood is oxygenated, according to knownnoninvasive optical monitoring techniques.

In another implementation, the pulse detection system is aphonocardiogram system for listening to the sound of the victim's heart,rather than a pulse oximetry system. The phonocardiogram system includesa microphone and an amplifier incorporated within the electrode pad.Because a heart sound can be confused with microphone noise, the signalprocessing that must be performed by the microprocessor inside thecontrol box will be more difficult in connection with a phonocardiogramsystem than in connection with a pulse oximetry system. Nevertheless,there are programs available that can enable the microprocessor todetermine whether an ECG signal is present as opposed to microphonenoise.

Pulse oximetry is a well-developed, established technology, but itrequires good contact between the light sources and the victim's skin sothat light can shine down into the victim's vascular bed. Many victimshave lots of chest hair, which can interfere with good contact. It maybe desirable for different types of electrode pads to be available at agiven location (one having a pulse oximetry system and one having aphonocardiogram system) so that a rescuer can select an appropriateelectrode pad depending on the nature of the victim.

In another implementation, instead of providing a low-profile buttonpanel, a button housing can be provided that is affixed to an edge ofthe defibrillation electrode. The housing may be in the form of aclamshell formed of single molded plastic element having a hinge at anedge of the clamshell around which the plastic bends. The two halves ofthe clamshell can be snapped together around the electrode assembly.

The resuscitation control box (FIG. 2 ) includes an internal chargestorage capacitor and associated circuitry including a microprocessor,an further includes off/on dial 28, and a “READY” button 30 that therescuer presses immediately prior to application of a defibrillationshock in order to ensure that the rescuer is not in physical contactwith the patient. The microprocessor may be a RISC processor such as aHitachi SH-3, which can interface well with displays and keyboards, ormore generally a processor capable of handling DSP-type (digital signalprocessing) operations.

The resuscitation control box has printed instructions 32 on its frontface listing the basic steps A, B, and C for resuscitating a patient andgiving basic instructions for positioning the defibrillation electrodepad on the patient. A speaker 32 orally prompts the user to performvarious steps, as is described in detail below.

For example, the resuscitation control box instructs the user, byaudible instructions and also through a display 34 on the resuscitationcontrol box, to check the patient's airway and perform mouth-to-mouthresuscitation, and if the patient's airway is still blocked, to pressthe A (Airway Help) button on the button panel (FIG. 1 ), upon which theresuscitation control box gives detailed prompts for clearing thepatient's airway. If the patient's airway is clear and the patient has apulse but the patient does not breathe after initial mouth-to-mouthresuscitation, the resuscitation control box instructs the user pressthe B (Breathing Help) button, upon which the resuscitation control boxgives detailed mouth-to-mouth resuscitation prompts. If, during thedetailed mouth-to-mouth resuscitation procedure, the rescuer checks thepatient's pulse and discovers that the patient has no pulse, theresuscitation control box instructs the user to press the C (CirculationHelp) button.

During the circulation procedure, the resuscitation control box receiveselectrical signals from the defibrillation electrodes and determineswhether defibrillation or CPR should be performed. If the resuscitationcontrol box determines that defibrillation is desirable, theresuscitation control box instructs the user to press the “ready” buttonon the resuscitation control box and to stand clear of the patient.After a short pause, the resuscitation control box causes adefibrillation pulse to be applied between the electrodes. If at anypoint the resuscitation control box determines, based on the electricalsignals received from the electrodes, that CPR is desirable, it willinstruct the user to perform CPR.

Thus, the key controls for the system are on the electrodes attached tothe patient rather than the resuscitation control box. This is importantbecause it enables the rescuer to remain focused on the patient ratherthan the control box. The resuscitation control box gets its informationdirectly from the electrodes and the controls on the electrodes.

The resuscitation control box can sense electrical signals from thepatient's body during pauses between CPR compressions. Also, as isdescribed below, a compression-sensing element, such as an accelerometeror other acceleration sensing element, or a force-sensing element isprovided in the region of the defibrillation electrode pad on which theuser presses to perform CPR. The purpose of the compression-sensing orforce-sensing element is to allow the resuscitation control box toprompt the user to apply additional compression or force, or to promptthe user to cease CPR if the user is performing CPR at an inappropriatepoint in time.

Referring to FIG. 4 , in one implementation, each electrode 12, 14 (onlyelectrode 12 is shown) of defibrillation electrode pad 10 includes apolymer-based ink containing a silver/silver-chloride suspension, whichis screen-printed on a polyester or plastic base 36. The ink is used tocarry the defibrillation current. The screen-printing process firstinvolves applying a resist layer to the polyester base 36. The resistlayer is basically a loose mesh of nylon or the like, in which the holeshave been filled in at some locations in the mesh. Then, thesilver/silver-chloride ink is applied as a paste through the resistlayer in a squeegee-like manner. The ink squeezes through the screen andbecomes a solid layer. The ink may then be cured or dried. Thesilver/silver-chloride ink provides good conductivity and goodmonitoring capabilities.

Thus, the ink can be applied as pattern, as opposed to a solid sheetcovering the entire polyester base. For example, U.S. Pat. No. 5,330,526describes an electrode in which the conductive portion has a scallopedor daisy shape that increases the circumference of the conductiveportion and reduces burning of the patient. A conductive adhesive gel 38covers the exposed surface of each electrode.

In addition, electrical circuit components are also be screen printed onthe base, in the same manner as flat circuit components ofmembrane-covered, laminated panel controls.

Referring to FIG. 3 , a rigid piece 40 of hard plastic, such as PVC orpolycarbonate, is laminated beneath substrate 36 and supports buttons A,B, C, and

PAUSE. The rigid plastic piece 40 is glued onto substrate 36. Buttons A,B, C, and PAUSE consist of small metal dome snap-action switches thatmake contact between an upper conductive ink trace 42 and lowerconductive ink traces 44, 46, 48, and 50. Buttons A, B, C, and PAUSEserve as controls that can be activated by the user that are physicallylocated either on or immediately adjacent to the electrode assemblyitself.

Each of buttons A, B, C, and PAUSE may be associated with an adjacentlight-emitting diode (LED). For example, LEDs may be glued, usingconductive epoxy, onto silver/silver-chloride traces on substrate 36. Anembossed polyester laminate layer 54 covers conductive ink trace 42 ofbuttons A, B, C, and PAUSE, and a foam layer 56 is laminated beneathrigid plastic piece 40.

Referring again to FIG. 4 , defibrillation electrode pad 10 includes anextension piece that is placed directly over the location on thepatient's body where the rescuer performs chest compressions. Thisextension piece includes substrate 36, and a semi-rigid plasticsupporting member 58 laminated underneath substrate 36 that covers thechest compression area. Semi-rigid supporting member 58 providessomewhat less rigidity than rigid plastic piece 409 provided at thelocation of buttons A, B, C, and PAUSE (illustrated in FIG. 3 ).

In implementations having a force-sensing element, a polyester laminate60, and a force-sensing resistor having two layers of carbon-platedmaterial 62 and 64, are laminated between polyester substrate 36 andsemi-rigid supporting member 58. A suitable construction of theforce-sensing resistor is illustrated in the FSR Integration Guide &Evaluation Parts Catalog with Suggested Electrical Interfaces, fromInterlink Electronics. The electrical contact between the twocarbon-plated layers of material increases with increased pressure, andthe layers of force-sensing resistive material can provide a generallylinear relationship between resistance and force. Conductive ink traces66 and 68 provide electrical connections to the two layers of theforce-sensing resistor.

During chest compressions, the rescuer's hands are placed over theextension piece, and the force-sensing resistor of the extension pieceis used to sense the force and the timing of the chest compressions. Theforce-sensing resistor provides information to the resuscitation controlbox so that the resuscitation control box can provide the rescuer withfeedback if the rescuer is applying insufficient force. Theresuscitation control box also provides coaching as to the rate at whichCPR is performed. In certain situations, the resuscitation control boxindicates to the rescuer that CPR should be halted because it is beingperformed at an inappropriate time, such as immediately prior toapplication of a defibrillation shock when the rescuer's hands shouldnot be touching the patient, in which case the resuscitation control boxwill also indicate that the rescuer should stay clear of the patientbecause the patient is going to experience a defibrillation shock.

As is noted above, during CPR the rescuer pushes on the patient's chestthrough the extension piece in the vicinity of the electrodes. If theresuscitation control box were to perform analysis during the chestcompressions, the chest compressions would be likely to affect thesensed electrical rhythm. Instead, during the pauses between sets ofcompressions (for example, the pause after every fifth chestcompression), the resuscitation control box can perform anelectrocardiogram (ECG) analysis. The resuscitation control box mightdiscover, for example, that the patient who is undergoing CPR isexperiencing a non-shockable rhythm such as bradycardia, in which casethe CPR is required in order to keep the patient alive, but then theresuscitation control box may discover that the rhythm has changed toventricular fibrillation in the midst of CPR, in which case theresuscitation control box would instruct the rescuer to stop performingCPR so as to allow the resuscitation control box to perform moreanalysis and possibly apply one or more shocks to the patient. Thus, therescuer is integrated into a sophisticated scheme that allows complexcombinations of therapy.

In another implementation, a compression-sensing element such as anaccelerometer may be used in place of a force-sensing element. Theaccelerometer, such as a solid-state ADXL202 accelerometer, ispositioned at the location where the rescuer performs chestcompressions. In this implementation, the microprocessor obtainsacceleration readings from the accelerometer at fixed time intervalssuch as one-millisecond intervals, and the microprocessor integrates theacceleration readings to provide a measurement of chest compression. Theuse of an accelerometer is based on the discovery that it is moreimportant to measure how deeply the rescuer is compressing the chestthan to measure how hard the rescuer is pressing. In fact, everyvictim's chest will have a different compliance, and it is importantthat the chest be compressed to a recommended depth in a normal sizedadult regardless of the victim's chest compliance.

FIG. 5 is a circuit diagram illustrating the circuit interconnectionsbetween the defibrillation electrode pad of FIG. 1 through the cable tothe resuscitation control box of FIG. 2 . Sternum electrode 14 isconnected to HV+ at the resuscitation control box, and apex electrode 12is connected to HV-. A ground GND is connected to the upper conductiveink trace of buttons A, B, C, and PAUSE and to one of the layers of theforce-sensing resistor. The other layer of the force-sensing resistor isconnected to CPR FORCE, and the lower conductive ink traces associatedwith buttons A, B, C, and PAUSE are connected to BUTTON_DETECT throughresistors R1, R2, R3, and R4. As an alternative to the use of aforce-sensing resistor, a compression-sensing accelerometer 76 may beemployed, in which case CPR_FORCE is replaced by CPR_ACCEL connected toaccelerometer 76. Red light-emitting diode 70, near-infraredlight-emitting diode 72, and photodetector diode 74 of the pulseoximetry system are connected to RLED, ILED, and ISENSE respectively, aswell as ground AGND. As an alternative to the use of a pulse oximetrysystem, a phonocardiogram system may be employed, in which case RLED,ILED, and ISENSE is replaced by SENSE connected to microphone 78 andamplifier 80.

FIGS. 6-9 illustrate the routine of the resuscitation system, which isbased on steps A, B, and C (airway, breathing, and circulation). Becausestep C includes defibrillation as well as chest compressions, all of theaspects of resuscitation are tied together in one protocol (actually, ifdefibrillation were considered to be a step D distinct from step C, thesequence of steps would be A, B, D, C).

The first thing the rescuer must do upon arriving at the patient is todetermine whether the patient is unconscious and breathing. The rescueropens the patient's airway, administers breaths to the patient if thepatient is not breathing, and checks to determine whether a pulse ispresent. If there is no pulse, rather than perform chest compressions asin standard CPR, the rescuer allows the resuscitation control box toanalyze the patient's electrical rhythm, and if the resuscitationcontrol box determines that the rhythm is shockable, the resuscitationcontrol box causes one or more shocks to be applied to the patient, andthen the rescuer performs chest compressions. Thus, there is provided afirst response system that can keep the patient viable until an advancedlife support time arrives to perform advanced techniques includingpacing, further defibrillation, and drug therapy.

If the resuscitation control box determines that it should apply one ormore defibrillation shocks to the patient, it is important that therescuer not be anywhere near the patient when the shocks are applied tothe patient. Prior to application of each shock, the resuscitationcontrol box instructs the rescuer to please press the “ready” buttonwhen everybody is clear of the patient. The pressing of the “ready”button verifies that the rescuer's hands are off of the patient.

When the resuscitation control box detects a shockable rhythm, theresuscitation control box provides shocks of appropriate duration andenergy (such as a sequence of shocks of increasing energy from 100Joules to 150 Joules to the highest setting, 200 Joules, with theresuscitation control box performing analysis after each shock todetermine whether another shock is required). If the defibrillationtherapy is successful, the patient's rhythm is typically converted fromventricular fibrillation, ventricular tachycardia, or ventricularflutter to bradycardia, idio-ventricular rhythm, or asystole, all ofwhich require CPR. It is rare to convert to a normal rhythm. Once theresuscitation control box has caused defibrillation shocks to be appliedto the patient, the resuscitation control box automatically senses thepatient's condition, and depending on the patient's condition willeither prompt the responder to perform CPR or will not prompt therespond to perform CPR.

Defibrillation equipment can be somewhat intimidating to rescuers whoare not medical professionals because the equipment can lead the rescuerto feel responsibility for having to save a loved one's life. It isimportant that the defibrillation equipment reduce this sense ofresponsibility. In particular, when the rescuer presses the “ready”button, rather than apply a shock immediately that will cause thepatient's body to jump dramatically, the resuscitation control box willthank the rescuer and instruct the rescuer to remain clear of thepatient and then wait for about two seconds (the resuscitation controlbox may describe this period to the rescuer as being an internal safetycheck, even if no substantial safety check is being performed). Thisprocess has an effect similar to a conversation that handsresponsibility to the resuscitation control box, which makes thedecision whether to apply the shock. Thus, the system maintains therescuer safety features of a semi-automatic external defibrillator,because the rescuer must press the “ready” button before each shock,while appearing to operate more as a fully automatic externaldefibrillator because the time delay immediately prior to each shockleaves the rescuer with the impression that operation of the equipmentis out of the hands of the rescuer. The use of CPR prompts incombination with the defibrillation also adds to the sense that therescuer is simply following instructions from the resuscitation controlbox.

With reference to FIGS. 6-9 , when the rescuer turns the resuscitationcontrol box on (step 101), the resuscitation control box first informsthe rescuer that the rescuer can temporarily halt prompting by pressingthe PAUSE button (step 102), and then, after a pause, instructs therescuer to check responsiveness of patient, and if the patient isnon-responsive to call an emergency medical service (EMS) (steps 103,104). The resuscitation control box then instructs the rescuer to checkthe patient's airway to determine whether the patient is breathing(steps 105-107).

After a pause, the resuscitation control box then instructs the rescuerthat if the patient is breathing the patient should be placed on thepatient's side, unless trauma is suspected, and that the rescuer shouldpress the PAUSE button (steps 108-109). Then the resuscitation controlbox instructs the rescuer to perform mouth-to-mouth resuscitation if thepatient is not breathing (steps 110-114). Then the resuscitation controlbox instructs the rescuer to press an Airway Help button A if thepatient's airway is blocked, so that the resuscitation control box cangive prompts for clearing obstructed airways (steps 115 of FIG. 6B and147-158 of FIGS. 9A-9B).

Next, after a pause (step 116 a), if the resuscitation control box doesnot include pulse oximetry or phonocardiogram capability (step 116 b),the resuscitation control box instructs the rescuer to check thepatient's pulse (step 117). After another pause, the resuscitationcontrol box instructs the rescuer to press a Breathing Help button B ifthe patient's pulse is okay but the patient is not breathing, so thatthe resuscitation control box can give prompts for assisting thepatient's breathing (steps 118 and 119 of FIG. 7A and 140-146 of FIG. 8). Light-emitting diodes adjacent the various buttons indicate whichbutton has been pressed most recently (only one light remains on at atime). The resuscitation control box next prompts the rescuer to contactan emergency medical system (step 120) and to open the patient's shirtor blouse and attach the adhesive pads (steps 122 f-122 h).

If the resuscitation control box does include pulse oximetry orphonocardiogram capability (step and 116 b), the resuscitation controlbox prompts the rescuer to open the patient's shirt or blouse and attachthe adhesive pads (steps 121 and 122 a). If the pulse oximetry orphonocardiogram system does not provide a valid pulsatile reading (step122 b), then the flow chart proceeds to step 117. If the pulse oximetryor phonocardiogram system does provide a valid pulsatile reading anddetects a pulse (steps 122 b and 122 c), then the resuscitation controlbox begins the breathing help routine (steps 122 d of FIG. 7B and step140 of FIG. 8 ). If the pulse oximetry or phonocardiogram system doesnot detect a pulse, then the resuscitation control prompts the rescuerto contact an emergency medical system (step 122 e), measures theimpedance of the patient to determine whether it is within an acceptablerange for application of shocks (step 123) and determines whether thepatient's rhythm is shockable (steps 124). If the rhythm is shockable,the resuscitation control box causes a sequence of shocks to be appliedto the patient, each shock requiring the rescuer first to press the“READY” button on the resuscitation control box (steps 124-131). Afterthe last shock in the sequence, or if the rhythm is non-shockable, theresuscitation control box prompts the rescuer in CPR (steps 132-139).The flowchart then returns to step 117.

FIG. 8 shows the steps 140-146 for prompting the rescuer to assist thepatient's breathing. After 12 breaths have been completed (step 144),the pulse oximetry or phonocardiogram system attempts to detect a pulse(step 145 a), or, if the system does not include a pulse oximetry orphonocardiogram system, the resuscitation control box prompts therescuer to check the patient's pulse. If no pulse is present, theresuscitation control box prompts the rescuer to press a CirculationHelp button C (step 145 b) that brings the rescuer back to thecirculation portion of the flowchart. Otherwise, if a pulse is detected,then the flow chart of FIG. 8 returns to step 142.

The combined defibrillation and CPR resuscitation assembly provided canbe less intimidating than conventional AEDs because the assembly is notdevoted solely to defibrillation. Moreover, the resuscitation assemblyis less intimidating because it accommodates common skill retentionproblems with respect to necessary techniques ancillary todefibrillation such as mouth-to-mouth resuscitation and CPR, includingthe appropriate rates of chest compression, the proper location forperforming compressions, the proper manner of tilting the patient'shead. In addition, because the rescuer knows that it may never even benecessary to apply a defibrillation shock during use of theresuscitation assembly, the rescuer may be more comfortable using theresuscitation assembly for mouth-to-mouth resuscitation and CPR. Unlikeprevious CPR prompting devices, the rescuer would be required to placethe electrode assembly on top of the patient, but the rescuer would dothis with the belief that the resuscitation assembly will be sensing thepatient's condition and that the likelihood that the resuscitationassembly is actually going to apply a shock is low. If, during thisresuscitation process, the resuscitation control box instructs therescuer to press the “READY” button so that a defibrillation shock canbe applied, the rescuer will likely feel comfortable allowing the shockto be applied to the patient. Basically, the resuscitation assemblysimply tells the rescuer what to do, and by that point, given that therescuer is already using the assembly, the rescuer is likely simply todo what the rescuer is told to do. Essentially, the rescuer will belikely to view the resuscitation assembly as simply being asophisticated CPR prompting device with an additional featureincorporated into it, and since rescuers are less likely to beintimidated by CPR prompting devices than AEDs, they will be likely touse the resuscitation assembly when it is needed.

FIGS. 10, 11, and 12A-12C show alternative implementations in which anelectrode pad assembly 10 is connected by a cable 212 to a first unit214 containing the electronics for CPR prompting and resuscitationcontrol. Another cable 216 connects the first unit to a second unit 218containing the electronics for defibrillation and pacing therapy. Athird cable 220 could be provided for making a direct connection fromthe second unit to the electrodes (FIG. 12B). The first unit 214 couldbe configured to receive the second unit 218 as an inserted module (FIG.12C), in which case the electrical connection between the units are madeinternally without the use of cable 216.

The primary function of the first unit 214 is to provide processing andcontrol for CPR functions such as CPR prompts. The primary function ofthe second unit 218 is to provide processing and control of electricaltherapy functions. The first unit includes a CPR processor 170, abattery 178, ECG circuitry 177 for amplifying and filtering the ECGsignal obtained from the defibrillation pads 12, 14, a microphone 78 forrecording the rescuer's voice as well as ambient sounds, anaccelerometer 76, a real time clock 187, and a speaker 182 fordelivering prompts to the rescuer. The second unit includes a therapyprocessor 171, a battery 179, buttons and controls 180, and memory 191.

The first unit could also be incorporated into the electrode padassembly rather than being a separate box. The electronics could beprovided on the rigid substrate 40 of the electrode pad assembly (FIG. 1).

Separate batteries 178, 179 and controls 180, 181 may be provided forthe first (CPR) and second (therapy) units, thereby allowing theelectronics in the first unit to provide CPR prompting to the operatorwithout the need for the second unit. The cable 216 that connects thefirst and second units may be detachable. Memory 189 is provided in thefirst unit for storing information such as voice recording, ECG data,chest compression data, or electronic system status such as devicefailures that occur during daily self checks of the electronicsinitiated by a real time clock circuit. The defibrillation electrode padassembly 10 may incorporate defibrillation

electrodes composed of a material that can be held against a patient'sskin for extended periods of time (e.g., up to 30 days).

As shown in FIGS. 13A and 13B, the pad assembly 10 may also incorporatefeatures on its upper surface facing the rescuer that provide a handle195 for the rescuer during performance of CPR. The handle could take theform of a fabric loop (FIG. 13B) or a more rigid polymer member (FIG.13A). The fabric could be sewn or adhered by adhesive or ultrasonicbonding to the pad 10 (FIG. 13B). The polymer handle could also bebonded by adhesive or ultrasonic bonding to the pad (FIG. 13A). It hasbeen shown in studies that the maintenance of pressure on the chestduring the decompression phase of chest compression results in asignificant decrease in the effectiveness of the chest compressions. Thehandle 195 motivates the rescuer to pull up at least slightly during thedecompression phase. The adhesive gel of the electrode pad, or otheradhesive, can extend under the region where the rescuer's hands areplaced during compression thus providing adhesion of the pad to the skinwhile the rescuer pulls on the handle during the decompression phase.Pulling up on the chest during the decompression phase has been shown toheighten negative intrathoracic pressure, increasing venous return andthus increasing blood flow during chest compressions.

In another implementation, the first unit may be adapted to be supportedby the patient for long periods of time. The unit could be incorporatedinto the electrode pad assembly as suggested above, or it could be aseparate unit configured to be worn by the patient. In such animplementation, the electronics of the first unit are designed to allowfor long term monitoring of the patient's condition via the ECG 177 andphysiological monitoring 176 circuitry. If a physiological condition isdetected that is deemed hazardous to the patient by the CPR processor170, based on analysis of the ECG and other physiological parameters, analarm is sounded to the patient via the speaker 182.

An activity sensor and associated circuitry can inform the CPR processorof whether the patient is moving. For example, accelerometer 76 couldserve as the activity sensor, and detect whether or not the patient ismoving. Patient motion may be detected using a variety of differentalgorithms, including, for example the following: The accelerationsignal is integrated over one-second intervals to provide an estimate ofvelocity. Velocity is integrated over the same one-second intervals toprovide an estimate of displacement. The root means square velocity iscalculated for each one-second interval. If either the RMS velocityexceeds 0.2 cm/s or the peak displacement exceeds 0.5 cm, the patient isdetermined to be moving.

If the algorithm determines that a cardiac emergency event is occurring,the first unit can send a message directly to a medical emergencyresponse system, such as 911. This can be done using a variety of knowncommunication techniques, e.g., Bluetooth, cellular phone, UltraWideband (UWB). If the activity sensor has determined that the patientis still moving during the cardiac emergency, the unit could also issuea prompt indicating, “Call 911 Immediately!”

The first unit will be able to determine the orientation of the patient,e.g., based on the accelerometer output. It can detect if a patient hasfallen down and initiate a message to the emergency system. It can alsodetermine whether the patient is lying on his back, the properorientation for doing CPR. Thus, a specific prompt can be provided tothe rescuer that tells them to roll the patient on their back prior tobeginning CPR, should the device detect an improper orientation of thepatient.

Other implementations may include signal analysis software forpredicting the risk of a heart attack. When a threshold is exceeded inthe value of that risk probability, a voice prompt may be provided tothe patient via the speaker 182 to contact the medical emergency system.By using the motion detection capabilities of the accelerometer tomeasure and track a patient's activity level (PAL), and combining theactivity level calculation with measurements of the ECG 177, e.g.,ST-segment elevation (STE), the first unit is able to provide apredictor of the risk of an impending heart attack or cardiac arrest. AnST segment elevation exceeding a threshold such as 300 microvolts on theECG provides an indicator of impending heart attack. In the preferredembodiment, ST segment elevation in the presence of increased physicalactivity is an indication of further risk of potential cardiac arrest.The calculation of risk probability may be accomplished by firstperforming a logistic regression of variables such as STE and PAL aspredictors of cardiac arrest within 24 hours. The calculation may takethe form of a linear regression equation such as

0.24 STE+0.12 PAL=RISK.

Alternatively, nonlinear regression may be performed to allow for amultiplicative term such as

0.24 STE+0.12 PAL+0.54 (STE*PAL)=RISK.

The multiplicative term heightens the importance of STE in the presenceof PAL.

Parameters such as STE, PAL and RISK may additionally be stored inmemory and multiple readings and calculations performed over time. Thesequence of readings may then be analyzed for trends in thephysiological state of the patient that can augment the RISK calculationtaken at a single point in time. For instance, if STE is found to besteadily rising over a series of readings, the voice prompt may betriggered sooner than at a fixed threshold of 300 microvolts.

Additionally, the ECG may be analyzed to determine the interval betweenadjacent R-waves of the QRS complexes and using this interval tocalculate heart rate variability as a running difference betweenadjacent R-R intervals. It is known that the R-R interval will varyfollowing an ectopic beat or ventricular premature contraction (VPC). Ina healthy heart, the R-R interval will decrease immediately followingthe VPC followed by a gradual return to steady state; a heart with anincreased risk of heart attack will show a decreased level ofvariability. This effect is sometimes called heart rate turbulence. Twovariables are calculated: (1) the Relative Change in R-R interval (RCRR)between pre- and post-VPB R-R intervals,

RCRR=(R-R pre-VPB−R-R post-VPB)/R-R pre-VPB

and (2) the slope of the change of R-R interval (SRR) while it isundergoing its post-VPB decrease. If the RCRR is non-negative and theslope SRR does not steeper than −2 ms/R-R interval then the patient isconsidered as at risk. Alternatively, the individual calculations may beincluded along with STE and PAL to create an integrated measurementvector as discussed in the preceding paragraphs. Other signal analysisalgorithms may incorporate analysis of heart rate variability in thefrequency domain, wavelet domain or using non-linear dynamics-basedmethods.

Since VPBs are often rare events, the defibrillation electrode pad 10may include circuitry to stimulate the patient with a single pulse oflow enough amplitude to cause a VPB without undue discomfort to thepatient, under the patient's control. An additional control is providedon the low-profile button panel 20 so that the patient may initiate thepulse under their control. Alternatively, the device is programmed toautomatically deliver the pulse at regular intervals such as at 24-hourintervals, at a time of day when the patient may conveniently haveaccess to the device, such as in the morning. While the pulse generator186 may be located in the second (therapy) unit, it is preferablycontained as part of the first (CPR) unit.

In another implementation, the activity monitoring capability of thefirst unit may be utilized so that the activity state of the patient iscontinuously monitored. Using the activity monitoring capability and areal time clock 187, the first unit may detect when a patient has wokenup in the morning. After there has been 10 minutes of regular motiondetected, the unit may prompt the patient that it would like to performa test. If the patient assents to the test indicated by a press of theTEST button on the low-profile button panel 20, the unit will send out asmall current pulse, preferably a 40 millisecond pulse of 75 mAamplitude that is synchronized to the patient's ECG so that it occursapproximately 200 mS prior to the R-wave and after the T-wave so as notto introduce any arrhythmias. The pulse will safely cause a VPB in thepatient which can then be used to measure the autonomic response to aVPB to provide regular calculations of the autonomic response to a VPBas measured by such parameters, though not limited to, STE and PAL, andproviding a daily update to the RISK calculation.

Additional physiological measurement, preferably that of blood pressure,may be incorporated into the RISK calculation. A sudden change insystolic or mean arterial blood pressure of greater than 10-15 points isindicative of an increased risk of cardiac arrest. In the preferredembodiment, the blood pressure measurement device would be a handheld,inflated cuff blood pressure device 188. The blood pressure cuff 188would have wireless communication capability with the CPR Processor 170and at the conclusion of each measurement, the blood pressure readingalong with a date and time stamp would be stored in memory 189 of theCPR Processor 170 for subsequent use in calculating RISK. This schemewould allow the patient to carry the small blood pressure cuff alongwith them during their daily activities and take blood pressuremeasurements at regular intervals without having to return home.Alternatively, the blood pressure measurement device may communicatewith the therapy processor and may additionally get power from and bephysically connected to the second (therapy) unit by a cable. Thepatient will then be required to take regular blood pressure readings atthe second unit, typically a larger device that may or may not beportable. Communication of the blood pressure readings may beaccomplished over a cable between the first (CPR) and second units(therapy) units, e.g., cable 216, or wirelessly, using such technologyas Bluetooth.

The second unit 218 may in some implementations be thought of as anenergy delivery unit (EDU), in which case it would incorporate adefibrillator 172, pacer 173, or other electrical therapy 174. In someimplementations, the EDU would be small and light enough to be worn in aharness or belt to be carried around continuously by the patient. TheEDU 218 may in some cases not contain a therapy processor 171, but be a“dumb” device that requires the controls provided by connection to theprocessor in the first (CPR) unit, e.g., on the defibrillator pad 10, inorder to deliver electrical therapy to the patient.

In some cases, the patient may not even own an EDU due to thesignificant costs inherent in the high-voltage components necessary. Thepatient would only own the first unit and defibrillator pad, as thecomponents incorporated in them are less expensive, e.g., they can bemanufactured from less-expensive, consumer-type electronics. In such acase, when the patient did not own the EDU, and had a heart attack, abystander or family member who encountered the cardiac arrest victimwould be prompted to begin CPR. It has been shown now in several studiesthat performing good CPR for extended periods prior to delivery of ashock is not detrimental to long term survival, and can in some casesincrease survival rates. CPR would thus begin with built-in promptingand when the paramedic arrives with the defibrillator it can beconnected to the pads to deliver the electrical therapy. If the first(CPR) unit is separate from the electrode pad assembly, the EDUconnection to the electrodes could be direct, or via a cable connectedto the first (CPR) unit. If the defibrillator is an EDU or othercompatible device, patient and performance data stored by the first(CPR) unit may be downloaded to the defibrillator.

Many other implementations of the invention other than those describedabove are within the invention, which is defined by the followingclaims. For example, the defibrillation pads 10, 12 may be separablefrom the CPR-prompting first unit and be connected at the time that theEDU is brought to the scene; the defibrillation pads may be connectedboth electrically and mechanically to the CPR-prompting first unit atthat time. A greater amount of the control functionality may be put intothe first unit, leaving essentially only the circuitry for providing thedefibrillation pulses in the second unit.

The first unit may be incorporated into the defibrillation electrode padassembly, or made a separate unit connected to the pad assembly by oneor more cables. The second unit may connect to the first unit by one ormore cables, or by a wireless connection. The defibrillation pulses maypass through the first unit (FIG. 12A), or be routed directly to thedefibrillation electrodes via one or more cables running from the secondunit to the electrodes (FIG. 12B). The second unit may connect to thefirst unit by being plugged into the first unit (FIG. 12C), without theneed for a cable (e.g., the second unit could be a defibrillation modulethat plugs into the first unit).

In some implementations the second (therapy) unit can provide pacingtherapy as well as defibrillation therapy. Pulse detection methods otherthan pulse oximetry and phonocardiogram may be employed. Any methodcapable of detecting a victim's pulse can be used for pulse detection.

Referring to FIG. 14 , in some embodiments, the electrode pad assembly10 can be connected by a cable 1401 to a treatment unit 1402 containingelectronics for delivering treatment to a patient 1400, such aselectronics for defibrillation and pacing therapy. For instance, thetreatment unit 1402 can be a defibrillator, such as an AED. Theoperation of the treatment unit 1402 can be controlled by a control unit1404, such as a mobile device. In the example of FIG. 14 , the treatmentunit 1402 is in wireless communication with the control unit 1404, e.g.,through a short-range wireless protocol such as Bluetooth® communicationor another type of wireless communication. In some examples, thetreatment unit 1402 can be in wired communication with the control unit1404, e.g., through a cable connection.

The treatment unit 1402 can act as a power source and can includeelectronic components, such as a battery, a capacitor, and otherelectronic components that enable the treatment unit 1402 to providetreatment to the patient 1400. The treatment unit 1402 can also includea communication module 1408, e.g., an antenna, for communicatingwirelessly with the control unit 1404. In some examples, the treatmentunit 1402 can include basic controls 1410, such as a power switch and ashock/analyze controller, that can be used by a rescuer 1414 to operatethe treatment unit 1402 without the control unit 1404.

The control unit 1404 can be a mobile computing device, such as a mobilephone (e.g., an iPhone®), a tablet (e.g., an iPad®), a wearablecomputing device such as a smart watch or glasses (e.g., a Glass®wearable computing device), or another type of mobile computing device.The control unit 1404 executes a software application 1412 (referred toherein as an “app”) that controls the operation of the treatment unit1402, provides information and instructions to a user 1414 of thecontrol unit 1404 (e.g., a rescuer), and receives input from the user1414. In some examples, the app can be a generalized app that enablesthe control unit 1404 to control various types of treatment units 1402,such as treatment units 1402 produced by various manufacturers. In someexamples, the app can be specific to one or more particular brands ormodels.

The app 1412 can receive status information about the patient from theelectrode pad assembly 10. In some examples, the control unit 1404 canreceive the status information directly from the electrode pad assembly10, e.g., through a wired or wireless connection with the electrode padassembly 10. In some examples, the control unit 1404 can receive thestatus information from the treatment unit 1402, which receives thestatus information from the electrode pad assembly 10.

The app 1412 analyzes the status information to determine the conditionof the patient 1400. For instance, the app 1412 can determine if thepatient's rhythm is shockable. If the rhythm is shockable, the app 1412can command the treatment unit 1402 to deliver a shock to the patient1400, e.g., automatically or upon approval by the user 1414. In somecases, the app 1412 can determine the appropriate energy and durationfor the shock and the appropriate number of shocks. If the rhythm is notshockable, the app 1412 can instruct the user 1414 to deliver CPR to thepatient 1400.

In some examples, the app 1412 can command the treatment unit 1402 toanalyze the status information and to deliver a shock to the patient1400 if appropriate, e.g., automatically or upon approval by the user.

The app 1412 communicates information and instructions to the user 1414,e.g., through visual, audio, or tactile communications. The app 1412 candisplay information and instructions as images and/or text on a displayinterface of the control unit 1404. In one example, the app 1412displays step-by-step instructions and simple figures to guide the userin delivering CPR to the patient. The app 1412 can provide audioinformation through speakers of the control unit 1404. In one example,the app 1412 speaks “Clear: Shocking Patient” prior to commanding thetreatment unit 1402 to apply a shock. In one example, the app 1412sounds a rhythmic tone (e.g., a beep) to assist the user in deliveringcompressions at the proper rate. The app 1412 can provide tactileinformation through a vibration component of the control unit 1404. Forinstance, the app 1412 can cause the mobile device 1404 and/or a unit onthe electrode pad assembly 10 to vibrate when a new instruction isdisplayed on the display interface.

Other ways of communicating with the user can also be used.

The app 1412 can also receive input from the user 1414. For instance,the user can tap the screen with his finger or a pointing device, suchas a stylus, to input information to the app 1412. In one example, theuser can tap an “Approve” button to approve the delivery of a shock tothe patient 1400. Information can also be received by other methods. Forinstance, the user can input information, such as information about thepatient, to the app through a keyboard or keypad of the control unit1404. The user can speak into a microphone and the app 1412 can usevoice recognition technology to recognize voice commands. For instance,the user can ask for more information or give a command to the app 1412,such as commanding the app 1412 to dial 9-1-1 to report an emergency. Insome examples, the user's speech can be processed by a speechrecognition program. Other forms of input can also be used.

In some examples, the app 1412 can operate in either a rescue mode or atraining mode. In rescue mode, the control unit 1404 communicates withthe treatment unit 1402 to provide treatment to a real patient 1400. Intraining mode, the user-facing operation of the app 1412 is similar tothe rescue mode operation of the app, but the control unit 1404 does notcommunicate with the treatment unit. That is, the app 1412 acts as asimulator that allows the user 1414 to interact with the control unit1404 as if he were in a real rescue situation. In some examples, thetraining mode can include a simulation component, which simulates theoperation of the app 1412 in a real rescue situation; and a teachingcomponent, which provides recorded instructions, demonstrations, videos,quizzes, or other approaches to teaching the user about the app 1412 orabout rescue techniques in general.

The app 1412 can offer multiple levels of operation to the user 1414.Each successive level can be targeted at users with greater experience.Thus, each successive level can provide access to a wider range ofcapabilities of the app. In addition, the prompts and instructions thatthe app 1412 provides to the user can depend on the level. For instance,in a basic mode directed to inexperienced users, only basic functions ofthe app 1412 can be accessed, and detailed instructions for how toproceed in a rescue situation can be provided. In an advanced modedirected to experienced professional users, a more complete set offunctions of the app 1412 can be accessed, and fewer instructions areprovided so as not to distract the user. In some examples, training modecan provide a teaching component associated with each level that isdesigned to teach the user about the capabilities of the app 1412 atthat level and associated rescue techniques.

In some examples, the app 1412 can access a stored indicator of theuser's proficiency on startup, and can run the appropriate level basedon the stored indicator. The indicator can be stored locally on thecontrol unit 1404 or in a remote data storage accessible through acommunications network, such as the Internet. In some cases, theindicator can be reflective of the user's history of using the app 1412,e.g., in rescue mode, training mode, or both. For instance, theindicator can reflect the level that the user has reached in trainingmode. In some cases, the indicator can be specified by the user or by athird party, such as the user's supervisor. In some examples, noindicator is stored and the app 1412 can prompt the user to enter hisproficiency on startup.

Referring to FIG. 15 , in operation, when the app is started up (1500),the app determines whether to run in rescue mode or training mode(1502). In some examples, the app can prompt the user to identify themode, e.g., by a voice command or by tapping a button on the displayinterface. For instance, if the user does not answer the prompt within aset period of time (e.g., ten seconds, thirty seconds, one minute, oranother period of time), the app can run in rescue mode by default. Insome examples, the app automatically run in rescue mode if it detectsthe presence of a treatment unit, such as an AED.

If the app runs in rescue mode, the app causes the control unit toestablish wireless communication with the treatment unit (1504). In someexamples, if the app detects the presence of a treatment unit, awireless connection can be automatically established. In some examples,the app requests user input, such as user approval to establish theconnection or user input to identify the treatment unit.

In both training mode and rescue mode, the user's proficiency isidentified by the app (1506). In some examples, the app can retrieve theindicator of the user's proficiency from local data storage on thecontrol unit or from an Internet-accessible remote data storage. In someexamples, the app can prompt the user to enter an indicator of hisproficiency.

Based on the user's proficiency, the app provides access to theappropriate level of operation (1508). Depending on the level ofoperation, the user can have access to various capabilities of the app,and instructions and information can be provided to the user asappropriate. Referring to FIG. 16 , in one example, the app can providefour levels of

operation: a basic level 1600, an intermediate level 1602, aprofessional level 1604 and an advanced level 1606. Each level providesaccess to some or all of the capabilities of the level(s) below it andadditional capabilities for that particular level. In some examples,more or fewer levels can be provided. In training mode, the teachingcomponent for each level can provide a curriculum that is designed toteach the user how to perform rescue techniques in coordination with theoperation of the app at that level, while the simulation componentallows the user to practice the operation of the app at that level.

In the example of FIG. 16 , the basic level 1600 is designed for layusers who have basic knowledge of compressions but little experience(e.g., users who have completed a basic CPR training course). At thebasic level, the app primarily acts as a prompting tool that providesthe user with detailed instructions for how to proceed in a rescuesituation. For instance, the app can provide a sequence of instructions,questions, and information to the user as text on the screen, audio, orboth. The basic level can offer automated 9-1-1 calling capability,rhythm capabilities for CPR, and feedback about compressions.

Referring to FIG. 17 , in one example set of instructions for the basiclevel 1600, the user is reminded to stay calm (1700) and informed that9-1-1 will be called automatically (1702). The user is instructed tocheck the victim's pulse (1704) and asked to indicate when he is readyto start CPR (1706), e.g., by tapping on the display interface or byspeaking a command. When the user responds that he is ready, the app1412 provides detailed, step-by-step CPR instructions (1708), includingproviding a rhythm for compressions. In some examples, the control unit1404 can act as a feedback device to provide feedback about thecompression speed, depth, or both, as described in U.S. patentapplication Ser. No. 13/788,720, the contents of which are incorporatedherein by reference.

At an appropriate point during CPR, the user is asked if an AED isavailable (1710). If not, the user is instructed to continue CPR asdirected (1712). If an AED is available, the user is provided withdetailed instructions for preparing the AED (1714), including turning onthe AED, opening the electrode pad package, and applying the electrodepad assembly to the victim.

Once the AED is prepared, the app analyzes the condition of the victimto determine if the victim's rhythm is shockable. When the appdetermines that the victim's rhythm is shockable (1716), the user isnotified to stand clear of the victim (1718) and the app automaticallysends a command to the AED to deliver a shock to the victim (1720),e.g., after receiving confirmation that the user is clear of the victim.That is, in this example, the basic level does not provide the useraccess to the AED controls within the app.

In some examples, the app can command the AED to analyze the conditionof the victim to determine if the victim's rhythm is shockable. When theAED determines that the victim's rhythm is shockable, the AEDcommunicates with the app, which notifies the user to stand clear of thevictim. The app can then instruct the AED to deliver a shock to thevictim, e.g., after receiving confirmation that the user is clear of thevictim.

Other information and instructions can also be provided at the basiclevel. For instance, the app can remind the user about personal safetyissues, such as wearing gloves or a face mask. The app can ask the userif there is another person available to help, and can provideinstructions to that other person.

Referring again to FIG. 16 , the intermediate level 1602 is designed forusers who have proficient knowledge of CPR and AEDs, e.g., users whohave completed AED training. At the intermediate level 1602, thecapabilities offered by the app are substantially the same as thecapabilities offered at the basic level, but fewer questions andinstructions are presented to the user so as not to distract the user.

Referring to FIG. 18 , in one example set of instructions for theintermediate level, the user is informed that 9-1-1 will be calledautomatically (1800). The user is instructed to check the victim's pulse(1802) and instructed to start CPR (1804). The app can provide a rhythmfor compressions (1806) during CPR. In some examples, the control unitcan act as a feedback device to provide feedback about the compressionspeed, depth, or both, as described in U.S. Patent Application SerialNo. 13/788,720, the contents of which are incorporated herein byreference.

At an appropriate point during CPR, the user is asked if an AED isavailable (1808). If not, the user is instructed to continue CPR asdirected (1810). If an AED is available, the user is instructed toprepare the AED (1812).

Once the AED is prepared, the app analyzes the condition of the victimto determine if the victim's rhythm is shockable. When the appdetermines that the victim's rhythm is shockable (1814), the user isnotified to stand clear of the victim (1816) and instructed to press the“Shock” button on the AED (1818) when clear of the victim. That is, inthis example, the intermediate level does not provide the user access tothe AED controls within the app. In some examples, the intermediatelevel does not provide the user access to

the AED controls within the app; the user is limited to using thecontrols on the AED itself. When the app detects that a shock should bedelivered to the victim, the app notifies the user to stand clear of thevictim (1814) and asks the user to press the “Shock” button on the AED(1816) when clear of the victim.

Other information, instructions, and capabilities can also be providedat the intermediate level. For instance, the app can respond to a userrequest for help by providing additional instructions about a particulartechnique (e.g., by providing step-by-step instructions for thepreparation of the AED).

Referring again to FIG. 16 , the professional level 1604 is designed forprofessionals, such as first responders, who have substantial trainingin CPR, AEDs, and general rescue techniques. For instance, policeofficers and fire fighters may generally operate the app at theprofessional level. At the professional level, the app provides fewinstructions to the user. For instance, the app can provide aninstruction to the user only as a reminder, e.g., if the app detectsthat the user has forgotten a step or if a particular step is a commonlyoverlooked step. The professional level app can offer AED controlcapabilities, such as a shock/analyze capability performed by the appitself and operable by the user. The professional level app can alsorespond to instructions from the user. For instance, the user can speakinstructions asking the app to communicate with a dispatcher to send aparamedic team to treat a potential heart attack. In addition, theprofessional level provides access to all of the capabilities availableat the basic and intermediate levels. Other information, instructions,and capabilities can also be provided at the professional level.

Referring to FIG. 19 , in one example operation of the app at theprofessional level, the user is instructed to start CPR (1900). The appcan provide a rhythm for compressions (1902) during CPR. In someexamples, the control unit can act as a feedback device to providefeedback about the compression speed, depth, or both, as described inU.S. patent application Ser. No. 13/788,720, the contents of which areincorporated herein by reference. In some examples, the app can providea rhythm and/or feedback only if requested by the user.

If the user does not turn on the AED, the user can be provided with aprompt to turn on the AED through the app (1904), e.g., by clicking ortapping on a button on the display interface or by speaking a command.The app presents a shock/analyze capability to the user, e.g., asbuttons on the display interface or as commands that can be spoken. Whenthe app receives the user's command to analyze, the app analyzes thevictim's condition (1906). If the app determines that the victim'srhythm is shockable, the app asks for the user's command to shock thevictim (1908), e.g., by presenting a visual, audio, or vibrationindicator that the rhythm is shockable. Upon receiving the user'scommand to shock (e.g., a tap on a button on the display interface or aspoken command), the app sends a command to the AED to deliver a shockto the victim (1910). That is, in this example, the professional levelprovides the user with access to AED controls within the app.

Referring again to FIG. 16 , the advanced level 1606 is targeted foradvanced users, such as paramedics or emergency medical technicians(EMTs), who have had substantial training and experience in emergencysituations, such as advanced life support training. The advanced levelprovides access to all of the capabilities available at the professionallevel, and likewise provides few instructions to the user.

In addition, the advanced level can allow the user to connect one ormore monitors to the control unit to gain a more detailed and accurateoverview of the victim's condition. For instance, the user can connect amultiple lead ECG to the control unit, such as a three-lead ECG, atwelve-lead ECG, an eighteen-lead ECG, or another type of ECG. Plotscorresponding to each of the leads of the ECG can be displayed on thedisplay interface. In some examples, plots corresponding to all of theleads can be displayed simultaneously and the user can scroll throughthe plots. In some examples, the user can request a plot, e.g., by avoice command (e.g., speaking the name of the lead) or by selecting theplot from a list of available plots.

Other information, instructions, and capabilities can also be providedat the advanced level. For instance, the advanced level can providerecording and charting capabilities, e.g., a data recorder that recordsECG traces or a voice recorder that records a paramedic's ongoing voicenarration of an emergency rescue situation.

Referring to FIGS. 20-22 , in some examples, a portable multiple leadECG package 2200 can be easily carried by a rescuer, e.g., in a backpackor supply pack. In the example of FIGS. 20-22 , the ECG package 2200 isfor a 12-lead ECG, but other types of ECGs are also possible. The ECGleads in the ECG package 2200 can be attached to the control unit 1404,e.g., to an input port of a mobile device. The portable ECG package 2200can be carried around by medical personnel, enabling those medicalpersonnel to have easy access to complex ECG equipment, without thedanger of damaging the ECG electrodes or tangling the ECG cables.

Referring to FIG. 20 , a cylindrical housing 2202 is formed of a rigid,durable material, such as a hard plastic. A pull tab 2204 is accessibleat a slit 2205 in the housing. For instance, the pull tab 2204 canprotrude through the slit 2205. In some examples, the pull tab 2204 is aplug configured to plug into a port of the control unit (e.g., a mobiledevice, such as a mobile phone or tablet). For instance, the pull tab2204 can be a mini-USB connector. In some examples, the pull tabincludes a cover (not shown) that protects the mini-USB connector. Thehousing 2202 can be of a size that is easily carried, e.g., within abackpack or purse. For instance, the housing 2202 can have a diameter ofless than about 2 inches, e.g., less than about 1 inch. The housing 2202can have a length of less than about 5 inches, e.g., less than about 3inches.

In some examples, the ECG package 2200 is provided enclosed in awrapper, e.g., to protect the integrity and cleanliness of electrodepads therein. For instance, the ECG package 2200 can be packaged in awrapper that provides a high moisture vapor barrier, such as a highmoisture vapor transmission rate (MVTR) material, e.g., a polyfoilsubstrate. In some examples, the housing itself 2202 is formed of amaterial that provides a high moisture vapor barrier. In some examples,the slit 2205 can be closed by a gasket material that allows the pulltab 2204 to be accessed but prevents moisture from entering the interiorof the housing.

FIGS. 21A and 21B show cutaway views of the ECG package 2200 and analternative example of an ECG package 2200 a. ECG cables 2206 arewrapped around one or more dispensers 2208. For instance, in theexamples of FIGS. 21A and 21B, the cables are wrapped around a core 2208that is oriented along the length of the housing 2202. In some examples,the core 2208 can be a roller that is fixed to the housing, e.g., byholders that allow the core to rotate relative to the housing. In someexamples, the core 2208 can be loose within the housing. A distal end ofeach ECG cable 2206 is connected to the pull tab 2204. The ECG cables2206 can have a length sufficient to connect the pull tab 2204 to thecontrol unit and to connect electrodes on the proximal end of the ECGcables 2206 to the victim. For instance, the ECG cables 2206 can have alength of about 36 inches, about 30 inches, about 24 inches, or anotherlength.

A chip 2214, such as a memory chip or a processor, located in or nearthe pull tab 2204 can store and/or process ECG data carried by the ECGcables 2206. For instance, the ECG signals transmitted through the ECGcables 2206 can be stored on the chip 2214 so that the signals can laterbe read and analyzed by a physician at a hospital. By storing thesignals on the chip 2214, the stored data can be easily transported tothe hospital.

When a rescuer pulls the pull tab, the ECG cables 2206 unwind from theirwrapped configuration around the core 2208 and can be pulled out of thehousing 2202. For instance, the core 2208 can spin as the pull tab 2204is pulled, thus releasing the ECG cables 2206. By storing the ECG cables2206 in this wrapped configuration, the chance of the cables tangling orbreaking during transportation and/or unwinding can be minimized.

In some examples (e.g., FIG. 21A), each ECG cable 2206 is independent ofthe other ECG cables, and the ECG cables 2206 join together at the pulltab 2204. For instance, each ECG cable 2206 can be wound around aseparate section of the core 2208. In some cases, the core 2208 can bebeveled at the winding position of each ECG cable 2206 to help keep thecables in place. In some examples (e.g., FIG. 21B), some or all of theECG cables 2206 are aggregated into a multi-cable ribbon 2210. Theribbon 2210 containing the ECG cables is wound around the core 2208 as asingle unit and can be unwound from the core as a single unit. Once theribbon 2210 is completely unwound, the individual ECG cables 2206 can bepulled apart.

In some examples, each ECG cable 2206 can be wound individually around acorresponding core that can rotate relative to the housing, such as aradially oriented core. Other configurations of ECG cables 2206 withinthe housing are also possible. For instance, each ECG cable 2206 can becontained within a package, such as a pouch, within the housing.

Referring to FIG. 22 , each ECG cable 2206 has an electrode pad 2212 atits proximal end. That is, when the ECG cables 2206 are wound around thecore 2208, the electrode pad 2212 is also wound around the core 2208.Once the length of the electrodes has been pulled out of the housing,the electrode pads 2212 are accessible and can be placed on the victimas appropriate. For instance, each electrode pad 2212 can include aconductive gel embedded within a self-adhesive pad that is connected tothe corresponding ECG cable 2206.

In some examples, the electrode pads 2212 are disposed directly on thecore 2208, which can be coated with a release liner, such as silicone,to enable the pads 2212 to be removed quickly and easily and with littleto no damage to the pads. In some examples, the electrode pads 2212 canbe protected by a release liner coating, such as silicone, which can beremoved by the rescuer after removing the pads 2212 from the core 2208and prior to placing the pads on the victim. In some examples, theelectrode pads 2212 are encased in a packaging, and the packagedelectrode pads 2212 are wound around the core 2208. For instance, thepackaging can be an envelope that provides a high moisture vaportransmission rate barrier, such as a polyfoil substrate.

In some examples, the ECG cables 2206 can be different lengths. Forinstance, in some cases, each individual ECG cable 2206 can be a uniquelength, such that as the ECG cables 2206 are unwound from the core 2208,each ECG cable 2206 can be pulled off of the core 2208 separately fromeach other ECG cable 2206. In some cases, two or more groups of ECGcables 2206 can be formed, the ECG cables 2206 in each group having aunique length. The lengths of the ECG cables 2206 can be set based onthe order in which each ECG cable 2206 is to be applied to the victim.For instance, the first ECG cables 2206 to be applied, such as the six Vcables, can be the shortest cables, and the last ECG cables 2206 to beapplied, such as the limb cables, can be the longest cables. In somecases, the electrode pads 2212 of ECG cables 2206 of different lengthsare less likely to stick together, thus improving the usability of theECG housing 2200.

Referring to FIG. 23 , in some examples, an ECG housing 2200 b includesa hinged door 2216 connected to the housing 2200 b by one or more hinges2218. The door 2216 can be opened to access the pull tab. Other openingmechanisms can also be used, such as a sliding door, a clam-shellopening mechanism, or another type of opening mechanism.

In some examples, the ECG package 2200 is a single-use, disposablepackage. In some examples, new ECG cables 2206 can be wound around thecore 2208 to reuse the ECG package.

Referring to FIG. 24 , to deploy the ECG package 2200, the housing 2202is removed from its packaging (2300), if present. For instance, awrapper enclosing the housing can be cut, torn, or otherwise opened.

The pull tab 2204 is pulled (2302) away from the housing 2202, causingthe ECG cables 2206 connected thereto to unwind from the core 2208. Thatis, the ECG cables 2206 are unrolled and pulled out of the housingthrough the slit 2205 (2304).

The electrode pads 2212 at the proximal ends of the ECG cables 2206 areunrolled and removed from the housing 2202 through the slit 2205 (2306).The electrode pads 2212 can be positioned at appropriate positions onthe victim (2308), such as on the chest, legs, and/or arms of thevictim. The pull tab 2204 can be connected to a control unit, such as amobile phone or tablet or another type of mobile device, or to anothertype of ECG-capable device. Once the electrode pads 2204 are positionedand the pull tab 2204 connected to the control unit (2310), ECG readingscan be viewed on a display interface of the control unit (2312).

The features described herein can be implemented in digital electroniccircuitry, or in computer hardware, firmware, software, or incombinations of them. The apparatus can be implemented in a computerprogram product tangibly embodied in an information carrier, e.g., in amachine-readable storage device, for execution by a programmableprocessor; and method steps can be performed by a programmable processorexecuting a program of instructions to perform functions of thedescribed implementations by operating on input data and generatingoutput. The described features can be implemented advantageously in oneor more computer programs that are executable on a programmable systemincluding at least one programmable processor coupled to receive dataand instructions from, and to transmit data and instructions to, a datastorage system, at least one input device, and at least one outputdevice. A computer program is a set of instructions that can be used,directly or indirectly, in a computer to perform a certain activity orbring about a certain result. A computer program can be written in anyform of programming language, including compiled or interpretedlanguages, and it can be deployed in any form, including as astand-alone program or as a module, component, subroutine, or other unitsuitable for use in a computing environment.

Suitable processors for the execution of a program of instructionsinclude, by way of example, both general and special purposemicroprocessors, and the sole processor or one of multiple processors ofany kind of computer. Generally, a processor will receive instructionsand data from a read-only memory or a random access memory or both. Theessential elements of a computer are a processor for executinginstructions and one or more memories for storing instructions and data.Generally, a computer will also include, or be operatively coupled tocommunicate with, one or more mass storage devices for storing datafiles; such devices include magnetic disks, such as internal hard disksand removable disks; magneto-optical disks; and optical disks. Storagedevices suitable for tangibly embodying computer program instructionsand data include all forms of non-volatile memory, including by way ofexample semiconductor memory devices, such as EPROM, EEPROM, and flashmemory devices; magnetic disks such as internal hard disks and removabledisks; magneto-optical disks; and CD-ROM and DVD-ROM disks. Theprocessor and the memory can be supplemented by, or incorporated in,ASICs (application-specific integrated circuits).

To provide for interaction with a user, the features can be implementedon a computer having a display device such as a CRT (cathode ray tube),LCD (liquid crystal display), or other type of display monitor fordisplaying information to the user and a keyboard and a pointing devicesuch as a mouse or a trackball by which the user can provide input tothe computer.

The features can be implemented on a mobile computing device, such as amobile phone, a tablet, a watch, glasses, or another type of mobilecomputing device. The mobile computing device can have a display devicesuch as a touch screen for displaying information to the user andreceiving input from the user. The mobile computing device can receiveinput from the user via the touch screen, a key pad, a microphone, oranother type of input device.

The features can be implemented in a computer system that includes aback-end component, such as a data server, or that includes a middlewarecomponent, such as an application server or an Internet server, or thatincludes a front-end component, such as a client computer having agraphical user interface or an Internet browser, or any combination ofthem. The components of the system can be connected by any form ormedium of digital data communication such as a communication network.Examples of communication networks include, e.g., a LAN, a WAN, and thecomputers and networks forming the Internet.

The computer system can include clients and servers. A client and serverare generally remote from each other and typically interact through anetwork, such as the described one. The relationship of client andserver arises by virtue of computer programs running on the respectivecomputers and having a client-server relationship to each other.

It is to be understood that the foregoing description is intended toillustrate and not to limit the scope of the invention, which is definedby the scope of the appended claims. Other embodiments are within thescope of the following claims.

1-35. (canceled)
 36. A system for providing defibrillation therapy to apatient, the system comprising: at least one treatment unit comprisingat least one capacitor for storing charge to provide the defibrillationtherapy; at least two electrodes configured to be electrically coupledto the at least one treatment unit, the at least two electrodesconfigured to be coupled with the patient's chest to receive electricalsignals from the patient, and to deliver the defibrillation therapy fromthe at least one treatment unit; and a control unit electrically coupledwith the at least one treatment unit, the control unit configured toprovide a control signal to the at least one treatment unit for causinga sequence of defibrillation shocks to be delivered to the patient. 37.The system of claim 36, wherein the electrical signals compriseelectrocardiogram (ECG) signals.
 38. The system of claim 36, wherein thecontrol unit is configured to measure patient impedance based at leastin part on the electrical signals.
 39. The system of claim 36, whereinthe control unit is configured to be cable connected to the at least twoelectrodes.
 40. The system of claim 36, wherein the control unit isconfigured to control a time of delivery of one or more of the sequenceof defibrillation shocks, to the patient.
 41. The system of claim 36,wherein the sequence of defibrillation shocks comprises a firstdefibrillation shock and a second defibrillation shock, the seconddefibrillation shock being delivered after the first defibrillationshock, and wherein the control unit is configured to control a time ofdelivery of the second defibrillation shock based at least in part on atime of delivery of the first defibrillation shock.
 42. The system ofclaim 41, wherein the time of delivery of the first defibrillation shockis based at least in part on a user selection on an interface of thesystem.
 43. The system of claim 41, wherein the time of delivery of thefirst defibrillation shock is based at least in part on a user pressinga button of the system.
 44. The system of claim 43, wherein the buttonis of the control unit.
 45. The system of claim 36, wherein the controlunit comprises at least one user-selectable control to turn the controlunit on or off.
 46. The system of claim 36, wherein the control unit isconfigured to provide visual prompts to a user.
 47. The system of claim36, wherein the at least two electrodes comprise at least one highvoltage apex electrode and at least one high voltage sternum electrode.48. A method for providing defibrillation therapy to a patient, themethod comprising: receiving electrical signals from the patient by atleast two electrodes coupled with the patient's chest, the at least twoelectrodes being electrically coupled with at least one treatment unitcomprising at least one capacitor for storing charge to providedefibrillation therapy; sending, by a control unit electrically coupledwith the at least one treatment unit, a control signal to the at leastone treatment unit for causing a sequence of defibrillation shocks to bedelivered to the patient; and delivering, from the at least onetreatment unit via the at least two electrodes, the sequence ofdefibrillation shocks to the patient.
 49. The method of claim 48,wherein receiving the electrical signals comprises receivingelectrocardiogram (ECG) signals.
 50. The method of claim 48, comprisingmeasuring, by the control unit, patient impedance based at least in parton the electrical signals.
 51. The method of claim 48, comprisingcontrolling, by the control unit, a time of delivery of one or moredefibrillation shocks, of the sequence of defibrillation shocks, to thepatient.
 52. The method of claim 48, wherein the sequence ofdefibrillation shocks comprises a first defibrillation shock and asecond defibrillation shock, the second defibrillation shock beingdelivered after the first defibrillation shock, and comprisingcontrolling, by the control unit, the time of delivery of the seconddefibrillation shock based at least in part on a time of delivery of thefirst defibrillation shock.
 53. The method of claim 52, wherein the timeof delivery of the first defibrillation shock is based at least in parton a user selection on an interface of the system.
 54. The method ofclaim 53, wherein the time of delivery of the first defibrillation shockis based at least in part on a user pressing a button of the system. 55.The method of claim 54, wherein the button is of the control unit. 56.The method of claim 48, comprising providing, by the control unit,visual prompts to a user.
 57. The method of claim 48, wherein thecontrol unit receives the electrical signals from at least one apexelectrode, of the at least two electrodes, and at least one sternumelectrode, of the at least two electrodes.